Quantification and diagnostic relevance of blood and heme-mediated inhibition of prion detection by RT-QuIC

Real-time quaking-induced conversion (RT-QuIC) is an ultrasensitive amplification assay for the detection of prions. The assay has shown exceptional performance in optimal laboratory conditions, on par with bioassay, and far surpassing current immunoassay diagnostics. However, efforts to apply RT-QuIC as a real-world diagnostic have been hampered by inconsistencies and unexpectedly low sensitivity in some field samples. This study aims to quantify and characterize the mechanism of inhibition from blood and its constituent parts, hemoglobin and heme-omnipresent components of most sample types. Such systematic evaluations of RT-QuIC inhibitory factors represent necessary steps toward the consistent and sensitive performance necessary for a field-applicable diagnostic assay.